Possible causes

– Faulty Throttle Actuator Control (TAC) module
– Throttle Actuator Control (TAC) module harness is open or shorted
– Throttle Actuator Control (TAC) module circuit poor electrical connection (loose or broken wires)

Tech notes

There is a factory service bulletin for the P2108 code on following Cadillac vehicles:

2006-2007 HUMMER H2
2006-2007 HUMMER H2 SUT

Factory Service Bulletin HUMMER OBDII Code P2108

When is the code detected?

The Engine Control Module (ECM) has detected an out of range condition between the predicted and actual throttle position

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– No throttle response

P2108 HUMMER Description

The Throttle Actuator Control (TAC) module contains data which is essential for proper TAC operation. The TAC module continuously test the integrity of this data. When the TAC module is unable to write or read data to and from Random Access Memory (RAM), or the TAC module is unable to correctly read data from the flash memory or and internal TAC module processor fault is detected and the Detected Trouble Code (DTC) is set.

HUMMER Technical Service Bulletins for P2108 code